It has been conventionally known to manufacture an alloy piece billet by pressing alloy pieces made of a light metal. Out of such methods for manufacturing an alloy piece billet, various manufacturing methods configured to enhance yield have been known.
It has been known that, for example, while an upper punch is brought into contact with pieces with which the interior of a die is filled to confine the pieces, a lower punch is moved relatively upward to the die to press the pieces from below, and subsequently, the upper punch is moved downward to further press the pieces, thereby forming a long green compact.
Furthermore, a method has been known in which, a first alloy billet, alloy pieces, and a second alloy billet are stacked in a die sequentially from bottom to top, the stack in the die is compressed under pressure such that alloy particles enter the first and second alloy billets, thereby producing an integrally formed long alloy billet.